Patent US3647455A successfully refreshed from Google Patents.
US3647455A
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Direct positive emulsions containing iodide ions and a sensitizing dye
Assignee: EIDP Inc
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Filing: 1969-10-13
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Granted: 1972-03-07
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Expires: 1989-10-13
Abstract
Abstract Preparation of silver halide emulsions by (a) adding 5-15 mg. per mole of silver halide of a water-soluble inorganic iodide to an aqueous redispersion of a precipitated, ripened and washed, water-permeable colloid silver chlorobromide or bromide emulsion, and (b) adjusting the pH to 5-9 and digesting the emulsion at 110* to 150* F. for about 15-60 minutes, there being added per mole of silver halide 0.00033 to 12.0 g. of an amine borane as a fogging agent; characterized in that after the digesting step, there is added per mole of silver halide approximately 10-100 mg. of an optical sensitizing dye.
Inventors
- 👤 Cortland Russell Burt
- 👤 Peter Anthony Ciavarri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:26
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/485; G03C1/48515; G03C1/48523; G03C1/4853
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
11 words
A process according to claim 1, wherein the colloid is gelatin.
Claim 2
Dependent Claim
13 words
A process according to claim 1, wherein the sensitizing dye is 4(1,3,3-trimethylindolidinyl) ethylidene-(3-methyl-1-p-sulfophenyl)-5-pyrazolone.
Claim 3
Dependent Claim
15 words
A process according to claim 1, wherein the sensitizing dye is 2(3-ethyl thiazolylidene) ethylidene-3 carboxymethyl-5-rhodanine.
Claim 4
Dependent Claim
13 words
A process according to claim 1, wherein the sensitizing dye is 4(p-dimethylbenzal) 3-methyl-1-p-sulfophenyl-5-pyrazolone.
Claim 5
Dependent Claim
15 words
A process according to claim 1, wherein the sensitizing dye is 3,3''(2-carboxyethyl)-5,6,5'',6'' tetramethyl benzoxazole carbocyanine.
Claim 6
Dependent Claim
47 words
A process according to claim 1, wherein the amine borane is an alkyl amine borane of the formula wherein R1 is an alkyl radical of 1-20 carbon atoms, and R2 and R3 are each taken from the group consisting of H and alkyl of 1-20 carbon atoms.
References Cited (Backward Citations)
US3249440A
Cited
US3367780A
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US3361564A
Cited
US3447852A
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US3445235A
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US3501309A
Cited
US3505070A
Cited
US3501312A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-03-07 | 1975-09-06 | 1976-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-07 | 1979-09-06 | 1980-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-07 | 1983-09-06 | 1984-03-07 | $7700.00 | Window Closed / Lapsed |